Astaneh Ali Vaziri, Urban Matthew W, Aquino Wilkins, Greenleaf James F, Guddati Murthy N
Department of Civil Engineering, North Carolina State University, Raleigh, NC 27695, United States of America. The Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, TX 78712, United States of America.
Phys Med Biol. 2017 Jul 7;62(13):5473-5494. doi: 10.1088/1361-6560/aa6ee3.
Arterial stiffness is found to be an early indicator of many cardiovascular diseases. Among various techniques, shear wave elastography has emerged as a promising tool for estimating local arterial stiffness through the observed dispersion of guided waves. In this paper, we develop efficient models for the computational simulation of guided wave dispersion in arterial walls. The models are capable of considering fluid-loaded tubes, immersed in fluid or embedded in a solid, which are encountered in in vitro/ex vivo, and in vivo experiments. The proposed methods are based on judiciously combining Fourier transformation and finite element discretization, leading to a significant reduction in computational cost while fully capturing complex 3D wave propagation. The developed methods are implemented in open-source code, and verified by comparing them with significantly more expensive, fully 3D finite element models. We also validate the models using the shear wave elastography of tissue-mimicking phantoms. The computational efficiency of the developed methods indicates the possibility of being able to estimate arterial stiffness in real time, which would be beneficial in clinical settings.
动脉僵硬度被发现是许多心血管疾病的早期指标。在各种技术中，剪切波弹性成像已成为一种有前景的工具，可通过观察导波的频散来估计局部动脉僵硬度。在本文中，我们开发了用于动脉壁中导波频散计算模拟的高效模型。这些模型能够考虑在体外/离体和体内实验中遇到的浸没在流体中或嵌入固体中的充液管。所提出的方法基于明智地结合傅里叶变换和有限元离散化，在充分捕捉复杂的三维波传播的同时，显著降低了计算成本。所开发的方法以开源代码实现，并通过与成本高得多的全三维有限元模型进行比较来验证。我们还使用组织模拟体模的剪切波弹性成像对模型进行了验证。所开发方法的计算效率表明有可能实时估计动脉僵硬度，这在临床环境中将是有益的。
